Water-soluble fluorescent Ag nanoclusters (NCs) were synthesized at room temperature with sodium dodecyl sulfonate (SDS) as a protective agent. The effects of synthetic conditions on the fluorescence properties of Ag NCs were investigated. The results show that the fluorescence intensity of Ag NCs strongly depends on the synthetic conditions, such as the molar ratio of AgNO3 versus SDS and sodi...

A series of pyrene-fullerene C60 dyads bearing pyrene units (PyFC12, PyFPy, Py2FC12 and PyFN) were synthesized and characterized. Their optical properties were studied by absorption and fluorescence spectroscopies. Dyads were designed in this way because the pyrene moeities act as light-harvesting molecules and are able to produce "monomer" (PyFC12) or excimer emission (PyFPy, Py2FC12 and PyFN)...

The fluorescence-detection techniques of cosmic-ray air-shower experiments require precise knowledge of atmospheric properties to reconstruct air-shower energies. Up to now, the atmosphere in desert-like areas was assumed to be stable enough so that occasional calibration of atmospheric attenuation would suffice to reconstruct shower profiles. However, serious difficulties have been reported in...

The fluorescence spectral characteristics and the interaction of several water-soluble metal complexes of Schiff-base with DNA are described. Among the complexes tested, Mn-Schiff-base bound to DNA showed a marked decrease in the fluorescence intensity with a blue shift of the excitation and emission peaks. Some hypochromism in the UV absorption spectra was also observed. KI quenching and compe...

Stable tetracoordinated organoboron complexes as classic fluorescent molecules have found various applications in material and medical sciences. A new class of curcumin-BF2 complexes has been prepared from the condensation of 2,2-difluoro-1,3-dioxaborylpentadione with a variety of aldehydes and its photophysical properties were characterized. Systematic variations were observed in the absorptio...

today, lasers are widely used in biology and medicine, and the majority of healthcenters and hospitals utilize modern laser systems for diagnosis and therapy applications.researchers have introduced different medical applications for different lasers used in surgeries and other medical treatments. medical lasers can be categorized in both diagnosis and therapy branches. main difference between ...

We provide a new and definitive spectral assignment for the absorption, emission, high-resolution fluorescence excitation, linear dichroism, and/or magnetic circular dichroism spectra of 32 chlorophyllides in various environments. This encompases all data used to justify previous assignments and provides a simple interpretation of unexplained complex decoherence phenomena associated with Qx → Q...

The fluorescence from a turbid medium such as biologic tissue contains information about scattering and absorption, as well as the intrinsic fluorescence, i.e., the fluorescence from an optically thin sample of pure fluorophores. The interplay of scattering and absorption can result in severe distortion of the intrinsic spectral features. These distortions can be removed by use of a photon-migr...

in this work facile sol-gel (pechni) method has been successfully established to synthesize zn4b6o13 nanocrystals which have cubic crystals with lattice parameter: a =7.48 a. the structure and morphology of the obtained material were studied by x-ray diffraction (xrd), infrared spectra (ir), scanning electron microscopy (sem) and photoluminescence analysis. the experimental results show a band ...

Chlorophyll a fluorescence can be used as an early stress indicator. Fluorescence is also connected to photosynthesis so it can be proposed for global monitoring of vegetation status from a satellite platform. Nevertheless, the correct interpretation of fluorescence requires accurate physical models. The spectral shape of the leaf fluorescence free of any re-absorption effect plays a key role i...